1. Field of the Invention
The present invention relates to a distributed printing system including a number of image forming apparatuses connected with each other, and more particularly relates to a distributed printing system that distributes and executes image editing.
2. Description of the Related Art
As it is widely demanded to make office work more efficient, it is also widely requested to improve productivity of image forming apparatuses such as a multifunction peripheral (MFP). Regarding this point, Japanese Patent Publication 2004-236210 (JP-2004-236210-A), a distributed printing system that a number of MFPs connected via a private or public network distribute and execute printing is described.
FIG. 7 illustrates a distributed printing system 500 described in JP-2004-236210-A. In the distributed printing system 500, MFP 502 and MFP 504 are communicably connected to each other via a private network 506. When a user prints 40 documents in booklet printing by using the distributed printing system 500, the MFP 502 (parent device) firstly scans the documents and generates 40 sets of image data. After that, the parent device executes consolidating (2 in 1) for 40 image data, generates 20 consolidated image data, and prints it out in booklet form. Meanwhile, the parent device sends the generated 20 consolidated image data to the MFP 504 (child device) in reverse order. After the child device that received the 20 consolidated image data from the parent device executes booklet printing for the 20 consolidated image data, the distributed printing system 500 finishes the whole printing.
There is merit in adopting architecture in which a MFP which scans documents executes all consolidating and a number of MFPs share only printing for the consolidated image data such as the consolidated printing system 500, provided that data sending time per unit image is much longer than image data consolidating time per unit image data (data consolidating time<<data sending time.) A description follows regarding this point.
In case architecture in which the parent device that scans documents sends image data to the child device and the child device consolidates the image data is adopted, the child device can not start consolidating until the child device finishes receiving all 40 image data, so the child device needs to store all the image data in its memory unit until transferring for all 40 image data finishes, and the child device can not release its memory resource for a long time in case data sending time is much longer than data consolidating time. By contrast, in architecture in which the parent device executes all consolidating, sends consolidated image data to the child device in reverse order, and requests the child device to print like the consolidated printing system 500, the child device can execute printing sequentially each time the child device receives consolidated image data from the parent device, and the child device can release its memory resource instantaneously and utilize its memory resource in more efficient way.
However, if data consolidating time is much longer than data sending time (data consolidating time>>data sending time), consolidating at the parent device becomes a bottleneck, so the productivity of the whole consolidated printing system 500 admits of further improvement.